Acidosis susceptibility affects feeding behavior of dairy cows

High-producing, mid-lactation dairy cows are not equally susceptible to sub acture ruminal acidosis (SARA) fed a high-grain diet. DMI during the first 2 h after feeding, milk fat percentage, and valerate proportion in the ruminal fluid were the variables with the greatest correlation with ruminal pH (P ≤ 0.05). These results indicate that substantial variation exists in SARA susceptibility among high producing, mid-lactation dairy cows, and that cows characterized as tolerant to the high-grain diet exhibit greater DMI and milk fat percentage, but decreased sorting behavior and proportion of isovalerate in the rumen.